LinkerId: Fix detection of linker tool without path

Some compiler drivers invoke the linker tool as just `ld`, with no path,
expecting it to be in the `PATH`.

Modules/CMakeParseImplicitLinkInfo.cmake

@@ -74,7 +74,7 @@ function(cmake_parse_implicit_link_info2 text log_var obj_regex)
   # whole line and just the command (argv[0]).
   set(linker_regex "^( *|.*[/\\])(${linker}|${startfile}|([^/\\]+-)?ld|collect2)[^/\\]*( |$)")
   set(linker_exclude_regex "collect2 version |^[A-Za-z0-9_]+=|/ldfe ")
-  set(linker_tool_regex "^[ \t]*(->|\")?[ \t]*([^\"]*[/\\](${linker}))(\"|,| |$)")
+  set(linker_tool_regex "^[ \t]*(->|\")?[ \t]*(([^\"]*[/\\])?(${linker}))(\"|,| |$)")
   set(linker_tool_exclude_regex "cuda-fake-ld|-fuse-ld=")
   set(linker_tool "NOTFOUND")
   set(linker_tool_fallback "")

Tests/RunCMake/ParseImplicitLinkInfo/results/craype-C-Intel-18.0.2.20180210.output

@@ -1,3 +1,3 @@
 libs=imf;svml;irng;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/2018.2.199/compilers_and_libraries_2018/linux/mkl/lib/intel64;/opt/intel/2018.2.199/compilers_and_libraries_2018.2.199/linux/compiler/lib/intel64_lin;/opt/gcc/6.3.0/snos/lib/gcc/x86_64-suse-linux/6.3.0;/opt/gcc/6.3.0/snos/lib64;/lib64;/usr/lib64;/opt/gcc/6.3.0/snos/lib;/lib;/usr/lib
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/craype-CXX-Intel-18.0.2.20180210.output

@@ -1,3 +1,3 @@
 libs=imf;svml;irng;stdc\+\+;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/2018.2.199/compilers_and_libraries_2018/linux/mkl/lib/intel64;/opt/intel/2018.2.199/compilers_and_libraries_2018.2.199/linux/compiler/lib/intel64_lin;/opt/gcc/6.3.0/snos/lib/gcc/x86_64-suse-linux/6.3.0;/opt/gcc/6.3.0/snos/lib64;/lib64;/usr/lib64;/opt/gcc/6.3.0/snos/lib;/lib;/usr/lib
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/craype-Fortran-Intel-18.0.2.20180210.output

@@ -1,3 +1,3 @@
 libs=hugetlbfs;AtpSigHandler;AtpSigHCommData;pthread;mpichf90_intel;rt;ugni;pmi;imf;m;pthread;dl;sci_intel_mpi;sci_intel;imf;m;dl;mpich_intel;rt;ugni;pthread;pmi;imf;m;dl;pmi;pthread;alpslli;pthread;wlm_detect;alpsutil;pthread;rca;xpmem;ugni;pthread;udreg;sci_intel;imf;m;pthread;dl;hugetlbfs;imf;m;pthread;ifport;ifcore;imf;svml;m;ipgo;irc;svml;c;gcc;irc_s;dl;c
 dirs=/opt/cray/pe/libsci/18.07.1/INTEL/16.0/x86_64/lib;/opt/cray/dmapp/default/lib64;/opt/cray/pe/mpt/7.7.3/gni/mpich-intel/16.0/lib;/opt/cray/rca/2.2.16-6.0.5.0_15.34__g5e09e6d.ari/lib64;/opt/cray/alps/6.5.28-6.0.5.0_18.6__g13a91b6.ari/lib64;/opt/cray/xpmem/2.2.4-6.0.5.1_8.26__g35d5e73.ari/lib64;/opt/cray/pe/pmi/5.0.14/lib64;/opt/cray/ugni/6.0.14-6.0.5.0_16.9__g19583bb.ari/lib64;/opt/cray/udreg/2.3.2-6.0.5.0_13.12__ga14955a.ari/lib64;/opt/cray/pe/atp/2.1.3/libApp;/opt/cray/wlm_detect/1.3.2-6.0.5.0_3.1__g388ccd5.ari/lib64;/opt/intel/2018.2.199/compilers_and_libraries_2018/linux/mkl/lib/intel64;/opt/intel/2018.2.199/compilers_and_libraries_2018.2.199/linux/compiler/lib/intel64_lin;/opt/gcc/6.3.0/snos/lib/gcc/x86_64-suse-linux/6.3.0;/opt/gcc/6.3.0/snos/lib64;/lib64;/usr/lib64;/opt/gcc/6.3.0/snos/lib;/lib;/usr/lib
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-C-Intel-18.0.0.20170811.output

@@ -1,4 +1,4 @@
 libs=imf;svml;irng;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/compilers_and_libraries_2018.0.128/linux/ipp/lib/intel64;/opt/intel/compilers_and_libraries_2018.0.128/linux/compiler/lib/intel64_lin;/opt/intel/compilers_and_libraries_2018.0.128/linux/mkl/lib/intel64_lin;/opt/intel/compilers_and_libraries_2018.0.128/linux/tbb/lib/intel64/gcc4.7;/usr/lib/gcc/x86_64-redhat-linux/4.8.5;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-C-Intel-2021.10.0.20230609.output

@@ -1,4 +1,4 @@
 libs=imf;svml;irng;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/oneapi/tbb/2021.10.0/lib/intel64/gcc4.8;/opt/intel/oneapi/mpi/2021.10.0/libfabric/lib;/opt/intel/oneapi/mpi/2021.10.0/lib/release;/opt/intel/oneapi/mpi/2021.10.0/lib;/opt/intel/oneapi/mkl/2023.2.0/lib/intel64;/opt/intel/oneapi/compiler/2023.2.1/linux/compiler/lib/intel64_lin;/opt/intel/oneapi/compiler/2023.2.1/linux/lib;/usr/lib/gcc/x86_64-redhat-linux/8;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-CXX-Intel-18.0.0.20170811.output

@@ -1,4 +1,4 @@
 libs=imf;svml;irng;stdc\+\+;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/compilers_and_libraries_2018.0.128/linux/ipp/lib/intel64;/opt/intel/compilers_and_libraries_2018.0.128/linux/compiler/lib/intel64_lin;/opt/intel/compilers_and_libraries_2018.0.128/linux/mkl/lib/intel64_lin;/opt/intel/compilers_and_libraries_2018.0.128/linux/tbb/lib/intel64/gcc4.7;/usr/lib/gcc/x86_64-redhat-linux/4.8.5;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-CXX-Intel-2021.10.0.20230609.output

@@ -1,4 +1,4 @@
 libs=imf;svml;irng;stdc\+\+;m;ipgo;decimal;cilkrts;stdc\+\+;gcc;gcc_s;irc;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/oneapi/tbb/2021.10.0/lib/intel64/gcc4.8;/opt/intel/oneapi/mpi/2021.10.0/libfabric/lib;/opt/intel/oneapi/mpi/2021.10.0/lib/release;/opt/intel/oneapi/mpi/2021.10.0/lib;/opt/intel/oneapi/mkl/2023.2.0/lib/intel64;/opt/intel/oneapi/compiler/2023.2.1/linux/compiler/lib/intel64_lin;/opt/intel/oneapi/compiler/2023.2.1/linux/lib;/usr/lib/gcc/x86_64-redhat-linux/8;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-Fortran-Intel-2021.10.0.20230609.output

@@ -1,4 +1,4 @@
 libs=ifport;ifcoremt;imf;svml;m;ipgo;irc;pthread;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/oneapi/tbb/2021.10.0/lib/intel64/gcc4.8;/opt/intel/oneapi/mpi/2021.10.0/libfabric/lib;/opt/intel/oneapi/mpi/2021.10.0/lib/release;/opt/intel/oneapi/mpi/2021.10.0/lib;/opt/intel/oneapi/mkl/2023.2.0/lib/intel64;/opt/intel/oneapi/compiler/2023.2.1/linux/compiler/lib/intel64_lin;/opt/intel/oneapi/compiler/2023.2.1/linux/lib;/usr/lib/gcc/x86_64-redhat-linux/8;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/linux-Fortran-IntelLLVM-2023.2.0.output

@@ -1,4 +1,4 @@
 libs=ifport;ifcoremt;imf;svml;m;ipgo;irc;pthread;svml;c;gcc;gcc_s;irc_s;dl;c
 dirs=/opt/intel/oneapi/tbb/2021.10.0/lib/intel64/gcc4.8;/opt/intel/oneapi/mpi/2021.10.0/libfabric/lib;/opt/intel/oneapi/mpi/2021.10.0/lib/release;/opt/intel/oneapi/mpi/2021.10.0/lib;/opt/intel/oneapi/mkl/2023.2.0/lib/intel64;/opt/intel/oneapi/compiler/2023.2.1/linux/compiler/lib/intel64_lin;/opt/intel/oneapi/compiler/2023.2.1/linux/lib;/opt/intel/oneapi/compiler/2023.2.1/linux/lib/clang/17/lib/linux;/opt/intel/oneapi/compiler/2023.2.1/linux/lib/clang/17/lib/x86_64-unknown-linux-gnu;/usr/lib/gcc/x86_64-redhat-linux/8;/usr/lib64;/lib64;/usr/lib;/lib
 library_arch=x86_64-unknown-linux-gnu
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/netbsd-C-GNU-4.8.5.output

@@ -1,3 +1,3 @@
 libs=gcc;gcc_s;c;gcc;gcc_s
 dirs=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/netbsd-CXX-GNU-4.8.5.output

@@ -1,3 +1,3 @@
 libs=stdc\+\+;m;gcc_s;gcc;c;gcc_s;gcc
 dirs=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/netbsd_nostdinc-C-GNU-4.8.5.output

@@ -1,3 +1,3 @@
 libs=gcc;gcc_s;c;gcc;gcc_s
 dirs=
-linker_tool=
+linker_tool=ld

Tests/RunCMake/ParseImplicitLinkInfo/results/netbsd_nostdinc-CXX-GNU-4.8.5.output

@@ -1,3 +1,3 @@
 libs=stdc\+\+;m;gcc_s;gcc;c;gcc_s;gcc
 dirs=
-linker_tool=
+linker_tool=ld